Combined carburetor and fume eliminator innerlock for internal combustion engines



g- 9 93 E. G PARVIN 2,171,291

COIBINED CARBURETOR AND FUNE ELIIINATOR INNERLOCK FOR INTERNAL COMBUSTION ENGINES Filed Nov. 17, 1958 4 Sheets-Sheet l ATTORNEY 5 Aug. 29, 1939. PARVIN 2,171,291

GOIBINED CARBURETOR AND FUME ELIIINATOR INNERLOCK FOR INTERNAL COMBUSTION ENGINES Filed Nov. 17, 1938 4 Sheets-Sheet 3 INVENTOR. fdward G. Fury? RNEYs,

Aug. 29, 1939. E, G. PARVlN 2,171,291

COMBINED CARBURETOR AND FUME ELIIINATOR INNERLOCK FOR INTERNAL COMBUSTION ENGINES Filed Nov. 17, 1938 4 Sheets-Sheet 4 INVENTOR. I Edward QTRn-vm ATTORNEYS Patented Aug. 29, 1939 I COMBINED GARBURETOR AND FUME ELIM- INATOR INNERLOCK FOR INTERNAL COM- BUSTION ENGINES Edward G. Parvin, Roselle, N. 1., assignor to National Pneumatic Company, New York, N. Y., a corporation of West Virginia Application November 17, 1938, Serial No. 240,948

10 Claims. (01. 123 -124) This invention relates to improvements in socalled fume eliminators as applied to internal combustion engines used particularly on heavy vehicles for the purposes of eliminating fuming and1 gassing thereof and maintaining the engine coo.

Speaking generally, a device of this nature automatically operates when the. carburetor throttle valve, and of course the accelerator pedal are at idling position, or are moved towards idling position and the engine is running at greater than idlingspeed; to open the intake manifold of an internal combustion engine directly to the atmosphere so as to by-pass the carburetor and supply fresh air directly to the cylinders. A device of this nature is disclosed in my copending application Serial No. 186,280, filed January 22, 1938, Patent No. 2,148,709, issued February 2, 1939.

In the actual use of a device such as disclosed in my above mentioned copending application it has been found that the operation of such systerms can be improved by providing a lock for the economizer and accelerating piston assembly of the carburetor to prevent the loss of the accelerating charge during the time of fresh air supply and the consequent spitting-and backfiring of the engine subsequent thereto upon acceleration because of the loss of that charge. The nature of this improvement will be apparent from the following description of the operation of the invention provided subsequent to a description of the structure of a complete system in accordance therewith.

This invention resides substantially in the combination, construction, arrangement and relative location of parts, all as will be set forth in full detail below.

Referring to the drawings,

Figure 1 'is a partly diagrammatic side elevational view of a system in accordance with this invention applied to the intake manifold of an internal combustion engine;

Fig. 2 is a vertical, central, longitudinal, crosssectional view through the fume eliminator portion of the mechanism;

Fig. 3 is a cross-sectional view partly in plan taken on the line 3-4 of Fig. 2;

Fig. 4 is a vertical, cross-sectional view through the economizer and accelerating piston assembly of a carburetor showing the lock of this invention applied thereto;

Fig. 5 is a horizontal, longitudinal, cross-sectional view through the lock cylinder showing a portion only of the carburetor;

Fig. 6 is a diagrammatic view of a modified arrangement for locking the economizer and accelerating piston assembly in closed position; and

Fig. 7 is a longitudinal, central, cross-sectional view through one of the check valves of the carburetor.

As illustrated in Figure 1 the intake manifold of an internal combustion engine is designated by the reference numeral I. Mounted thereon in accordance with common practice is a carburetor 2 provided with an air inlet strainer 3. The carburetor as illustrated is of the down draft type. At 4 isthe carburetor throttle valve shaft to which is secured a lever 5 extending radially therefrom in both directions. The lower end of the lever is pivotally connected by a link 6 to a bell crank l pivotally mounted on a shaft 8 below the floor board of the vehicle and in turn connected by a link 9 to the acceleratorpedal l mounted on the floor board. The other end of lever S is pivotally connected by link I l to an arm l2 on a shaft l3 which operates mechanism to be described in detail later. At i4 is shown the air inlet valve which is mounted on the intake manifold l by means of a suitable coupling fixture I". At I1 is a housing for the remainder of the mechanism which will be described in detail later, while at I8 is shown the pressure fluid supply pipe to a control valve within the housing [1. At 19 is a housing for a bellows member which operates the control valve as will be explained in detail below. The pipe 20 extends from the control valve to the pneumatic lock mounted on the carburetor and not shown in Figure 1.

. Referring to Fig. 2 there will be seen in crosssection all the mechanism comprising and associated with the air inlet valve 14, the bellows mechanism, and the pressure fluid supply control valve. In this figure a portion of the intake manifold is shown at I provided with an air inlet opening I in alignment with an opening in the coupling fixture l Mounted on the coupling fixture isthe air inlet valve l4 comprising a housing 2| formed to provide a cylinder in which a piston 22 is mounted for sliding movement vertically. The piston is hollow as shown and within it is a valve stem 25 on the upper end of which is secured a seat 24 for a spring 23 which lies between it and the lower end of the cylinder. 0n the lower end of the valve stem 25 is a. valve 26 arranged to rest on a seat 21 and close the passage through the seat from the air inlet opening 28. The casing 2| is formed so as to have the extension housing It on which the strainer I is mounted as shown.

At 28 is a passage in the portion ll of. the housing opening into the cylinder 2|. Mounted on the botimm wall of the portion ll of the housing is the pressure fluid control valve comprising a housing 30 having a longitudinal bore therethrough of various diameters as shown. The outer larger end of the bore is closed by a cap screw 3| and the bore is'divided into several chambers by means of the apertured plugs 32 and 33. Extending through the apertured plugs of the valve housing is a valve stem 38 which has a pair of opposed valves 33 and 35 thereon arranged to cooperate with seats on the plugs 32 and 33 respectively. The space to the right of plug 32 is open to the atmosphere through the exhaust passage 31. The space between the plugs 32 and 33 is connected by a passage in the valve casing 30 which forms a continuation of the passage 29 in the cylinder 2|. The space between these plugs is also open through a passage 20' (see also Fig. 3) into which one end of the pipe 20 extends. The space between the screw cap 3| and the plug 33 is in communication with a threaded passage l3 to which one end of the pressure fluid supply pipe I8 is connected. A spring 36 is provided engaging the valve stem 38 to hold it in the position shown so that valve 35 is seated and valve 34 is unseated.

The right hand end of the valve stem 33 proiects out of the end of the casing 30 and engages a lever 39 pivotally mounted at its upper end at ion the casing 30. This lever extends down into the air inlet casing l6 and has threadedly mounted thereon a stud ll provided with a disc 32. A tightening screw is provided to lock the stud II in adjusted positions. The interior of the inlet casing 60 is shaped as indicated at 43 to provide a converging construction adjacent the end of the casing supplying air to the valve 26. It will be noted that the further the disc 32 moves to the left in the converging direction of the portion 43 the more it closes it 011'. When it is at its extreme left hand position it most nearly closes it off, but it is to be noted it never completely closes this passage. The reason for this will be described later, although it is set forth in full detail in the above entitled application.

At 45 is a spring interposed between the housing and the lever 39 to urge it towards the position shown in Fig. 2. At 46 is a short lever secured to the shaft l3 within the housing and provided with a projection 33 adapted to engage the lever 39 which action is insured by a spring 31.

Referring now to Figs. 2 and 3 there is shown at 39 a bar which extends between and is connected to a pair of rods 50. This bar 43 extends transversely of the lever 33 as shown. The rods 50 extend into the housing I! through passages as shown in Fig. 2, which permit unrestricted longitudinal movement thereof. These rods are connected to a disc 5i which in turn is connected to and forms a seal with a bellows 52. The other end of the bellows is clamped between the housing l9 and a cap 53 so that the space within the bellows, in conjunction with the disc 5| and cap 53, is a closed or sealed chamber. Fixedly mounted on the disc ii at its center is a rod 54 which is encircled by a spring 55 lying between the end wall of the casing I! and a washer 56 held on the rod 54 by a nut as shown.

Extending upwardly through the wall of the cylinder 2| is a passage 51 which communicates with a longitudinally extending passage 53 in the portions i1 and I! of the housing. The passage I3 terminates in a port 53 in the cap 33 thereby opening into the chamber formed by the bellows.

Referring to Figs. 4 and 5 a portion of a carburetor having a vacuum actuated economizer 5 and accelerating piston assembly is shown, also showing the pneumatic lock therefor in accordance with this invention. The portion of the. carburetor illustrated is that of a down draft carburetor which is shown having the usual fuel chamber 60. This chamber is in communication with a smaller chamber 64 in the carburetor wall through a check valve I in accordance with well known practice. Mounted in the bottom of chamber 64 is another valve frequently called an -economizer valve which is in communication with the power and accelerating jet 33 of the carburetor. At 65 is a piston mounted for sliding movement in the chamber 64 and engaged by a spring which is shown in its'compressed state so that it is tending to move the piston 65 downward. Connected to the piston is a piston rod 66 which terminates in another piston 61 at the upper end of the chamber 64. The other end of this chamber is in communication at the passages 69, I0 and H with the mixing chamber of the carburetor. The space between the passages 35 and 61 is open to the mixing chamber of the carburetor through a passage l2.

The check valve ii is shown enlarged in Figure 30 7. The passage 6| which it controls is enlarged at its left hand end as shown and internally threaded to receive a plug 6 I which has a passage 6 l therethrough. A valve member 6 l is mounted in the little chamber thus formed and is provided 3 with a spring 6| to hold it against the inner face of the plug 6| to seal the passage 6| therethrough. The valve disc 6| is provided with a guiding tail piece 6| which in cross-section is in the form of a spider web or cross or as to crossposition the valve disc without interfering with the flow of gasoline therearound. When the piston 65 moves upwardly a suction condition is created below it, causing the valve il to open so that gasolinemay flow into the chamber '34. When the piston 65 descends the gasoline in the chamber 84 may not escape because the spring 6i holds the valve6l so as to close the passage ii and of course in addition the gasoline will help to create a pressure to hold it seated.

Mounted on the fuel supply chamber ill is a pneumatic lock comprising a cylinder I3 with a closure cap 12 having a threaded inlet passage 20" to which the other end of the pipe 23 is connected. Within the cylinder 13 is a piston ll 5 which is engaged by a spring Ii to hold it in the position shown in Fig. 5 when there is no pressure in the cylinder. The piston is provided with a piston rod which extends through the end of the cylinder 13 and is provided with a reduced portion I4 which moves in a passage in the wall of chamber 64 of the carburetor. It will be seen that the reduced portion I4 may be projected into the chamber 64 when pressure is applied to the piston 15 so as to engage under the enlarged head of the piston 61 to hold it in its uppermost position against the action of spring 68, as will be described at the proper place.

The operation of the system will be first briefly described without reference to the innerlock feature of the invention. If it be assumed that a vehicle driven by an internal combustion engine with the invention herein disclosed attached is operating say at 40 miles an hour and the operator removes his foot from the accelerator pedal n. a will be an that in accordance with usual practice the carburetor throttle valve will move back to fully closed position.

ture. If the clutch is left engaged it is apparent that the vehicle will be driving the engine at a ,speed greater than idling speed. Under these conditions it is the basic purpose of a system of this type to by-pass the carburetor and supply adequate quantities of fresh air directly into the intake manifold so that the engine is pumping non-explosive, substantially atmospheric air. At the same time, referring to Fig. 2, the link It will rotate lever 43 through shaft l3 away from the arm 39, leaving it free thereof and compressing spring 41. Under idling conditions, that is where the fuel mixture supply is reduced to an idling quantity, the pressure in the intake manifold I will fall with the result that the pressure in pas-- sages 59 and II and the chamber formed by the bellows 52 will also fall to substantially'the same value. As the space around the bellows 92 within chamber I9 is opento the atmosphere through the passages around the rods III and $4 (the portion I! of the casing notbeing sealed as shown for example in Fig. 2 where the closure plate ll does not flt tightly around the tubular extension forming the casing for the passage l3), the bellows 32 will contract moving plate It to the left, Fig. 2. Since the rods 50 are connected to this plate they likewise move to the left as does rod 54, comsure conditions within the intake manifold I it is apparent that air will rush through the strainer I, the casing l6, passage 23, passed valve 23 into the intake manifold through an opening I. Thus the cylinders get fresh air directly through this route, by-passing the carburetor and reducing what mixture comes from it to a non-explosive mixture.

It will be noted that the clockwise movementof lever 69 has moved the disc 42 towards the smaller end of the portion 43 of the air inlet passage so that the air rushing passed the discv around the edges thereof creates a pressure thereon which tends to hold the lever 39 in this new position. These conditions continue to exist while the vehicle speed falls until it approaches substantially idling speed. Of course as the engine speed falls the quantity of air, and hence its rate of movement passed the disc 43 into the intake manifold gradually falls. Atthe same time the pressure in the intake manifold gradually rises, and as a result the pressure in theibellows 52 gradually rises so that the bellows expands moving bar 49 towards the right away from the actuated lever 39. At Just about idling speed for the engine the parts being proportioned and spring 45 having been properly selected, the lever 39 will move back to the position shown in Fig. 2. In other words, whatever pressure is created by the air rushing in passed the disc 42 at reduced speed, is not suiflcient to hold the lever in its actuated position against the resistance of spring 45.

The return of lever 39 to the position shown in At this time the 'engine will be simply. receiving an idling mix-- P18. 2 releases the valve stem 33 so that the spring 33 can move'it back to the right seating valve 33 and unseating valve I4.- The seating of valve 33 cuts 01! the supply of air to the cylinder 2| and opens it to exhaust through plug 32 and exhaust passage 31. Thus spring 23 snaps valve 23 onto its seat and cuts oi! the supply of air through the housing l3. The engine is now back in its normal condition getting the idling mixture from the carburetor and it therefore resumes its normal operation. It will be apparent that if after the throttle is at idling position but the speed has not yet fallen to idling speed, the operator should depress the accelerator pedal it, it is of course necessary to close valve 23 so that the engine can operate normally. This is a very frequent condition on the road and to insure that the valve 28 is immediately closed the lever 43 is provided to push the lever 39 back to the position shown in Fig. 2, without any time lag. This occurs of course because of the connecting link ii.

In the operation of a system of this type where the carburetor employed is of the type which employs a suction operated economizer and accelerating piston assembly as herein disclosed it has been found, as will be obvious, that at the time valve 29. is open the pressure in the intake manifold and in the carburetor falls substantially to atmospheric pressure so that the vacuum condition within the carburetor is not high enough to hold the piston 61 in the position shown in Fig. 4. The result is that it falls down. opening valve 62 and permitting the discharge of a portion if not all of the accelerating charge of gasoline in the chamber 64 below the piston 65, through the jet 63. Then when the accelerating pedal is de-,

pressed and the carburetor throttle valve thereby opened for acceleration, there is no accelerating charge of gasoline available to meet the carburetor demand. Modern automobile engines are so designed today as to depend upon this accelerating charge and hence when a system as described above is applied to an engine having a suction operated assembly of this type, theengine tends to spit when the throttle valve is opened from idling position, and in addition it does not produce the power that it should. Furthermore. it will be apparent that the accelerating charge of gasoline is lost by this action which of course represents a waste, which is undesirable.

For this reason the. latch or lug I4 is provided with the piston 15 in the cylinder 13 to move itinto locking position at the time the previously described mechanism operates to open valve 28.. ,Thus every time valve 34 seats and valve-35 unseats to supply air to the cylinder 2| air is also supplied through the port 20' (Fig. 2) and pipe 20 (Fig. 1) to move the piston 15 (Fig. 5), to the right so that the latch or lug 14 moves under the rim of the enlarged upper end of the piston 61 (see Fig. 4). The result is then that when the pressure falls in the carburetor as it will when valve 26 is open, the pressure will also fall in passages ll, and 69, but the piston assembly cannot be moved down by spring 69 because it is held by the latch I4. 'Thus the accelerating charge in the chamber 64 remains there and is available when the accelerating pedal is depressed to perform its intended function. It is hardly necessary to point out, as ,the portion of the carburetor illustrated in Fig. 4 is well known'in the art, that the check valve 6i merely permits the flow of gasoline from the chamber 60 into the chamber 64 when the piston assembly 61 moves up so as to fill the chamber 64. At this time of course valve 62 is closed. When the piston assembly 61 moves down at the time of acceleration check valve 6| closes so that the fuel in chamber 64 cannot beforced back into chamber 66.,r'The result is that valve 62 opens and the charge is fed through the jet 63 into the carburetor.

It is of course apparent to those skilled in the art that the details of this invention may be widely modified. For example, instead of looking the piston 61 in its closed position by means of a directly acting pneumatic lock, various forms of electro-magnetic locks can be employed. For example there is shown one form of electromagnetic lock in Fig. 6. In this case the piston 61 is provided with an extension "iii of magnetizable metal such as iron to form the movable core of a solenoid winding IOI. This winding is in circuit with a suitable current source I62, and a switch including a movable contact 14'. This contact is mounted on the piston rod 14. This provides an air operated switch in which the cylinder 13 with its piston and pressure fluid sup.- ply pipe 26 is of exactly the same construction as the arrangement previously described and illustrated for example in Fig. 5. In other words, instead of the piston rod 14 forming a latch for direct cooperation with the piston 61 it is made part of a switch. The pipe 20 is connected as in the previous arrangement so that fluid pressure is supplied to the cylinder 13 atthe same time as it is supplied to the cylinder 2|. Thus every time the valve 26 opens the switch 14' closes completing the circuit to the winding l M and holding the piston 61 in its seated position so as to hold it and theparts connected thereto in the position shown in Fig. 4.

From the above description it will be apparent to those skilled in the art that this invention may be embodied in other physical forms without departure from the novel subject matter herein disclosed. I do not, therefore, desire to be strictly limited to the disclosure as given for purposes of illustration, but rather to the scope of the appended claims.

What I seek to secure by United States Letters Patent is:

1. In a system of the type described the combination with the intake manifold of an internal combustion engine and a carburetor connected thereto having a vacuum operated economizer and accelerating piston assembly therein, of means for simultaneously introducing fresh air directly into the intake manifold of the engine when the throttle valve of the carburetor is at or moved towards idling position and the engine is operating at greater than idling speed, and looking the economizer and accelerating piston assembly of the carburetor against movement.

2. In a system of the type described the combination comprising the intake manifold of an internal combustion engine, a carburetor con-. nected thereto having a throttle valve and a vacuum lifted accelerating piston assembly, valve means for supplying fresh air directly to the intake manifold, means for opening said valve when the throttle valve of the carburetor is at idling position and the engine is operating at greater than idling speed, and means for holding the accelerating piston assembly in the vacuum lifted position while said valve means is open,

3. The combination with the intake manifold of an internal combustion engine, a carburetor having a throttle valve connected thereto and a valve for supplying air directly into the intake manifold, of means controlled by the pressure conditions in the intake manifold for operating.

said valve, means in the air stream to said valve for holding said last mentioned means actuated until the speed of the engine approaches idling speed, and means actuated with the throttle valve of the carburetor for moving said last means to release said first means when the throttle valve is opened.

4. The combination with the intake manifold of an internal combustion engine, a carburetor connected thereto having a throttle valve and a valve for supplying air directly into the intake manifold, of pressure fluid actuated means connected to the intake manifold for operating said air inlet valve, means controlled by the movement of air to the intake manifold for maintaining said last mentioned means actuated until the engine speed approaches idling position, and means actuated with the throttle valve of the carburetor for moving said last means to release the fluid pressure actuated means when the throttle is opened from any position.

5. The combination with the intake manifold of an internal combustion engine, a carburetor connected thereto having a throttle valve, accelerator means for operating said throttle valve, and a pressure fluid operated inlet valve for controlling the supply of fluid under pressure to an exhaust from said inlet valve, of pressure fluid operated means connected to the intake manifold for operating said valve, means in the stream of air supplied to the manifold through the inlet valve for holding said air valve operated until the engine speed falls to idling speed, or to speed corresponding to a retarded position of the carburetor throttle valve, and means also actuated by said carburetor means for returning said last mentioned means to inoperative position upon movement of the throttle valve from any position to a more open position. 1

6. The combination with the intake manifold of an internal combustion engine and a valve for supplying air thereto, of means controlled conjointly by the pressure conditions in the intake manifold and the accelerator for opening said valve, means controlled by the flow of air to the intake manifold for maintaining the air inlet valve open until the engine .speed falls substantially to idling speed, and manually operated means for returning said last means to inoperative position.

'7. The combination with the intake'manifold of an internal combustion engine, a carburetor connected thereto having a throttle valve, actuating means for the throttle valve, and an air inlet valve for supplying air directly to the intake manifold, of means controlled by the pressure conditions in the intake manifold for opening said air inlet valve when the carburetor throttle valve is returned to or moved towards idling position, means controlled by the flow of air to the intake manifold for holding said pressure controlled means actuated until the engine falls to a speed corresponding to the throttle opening, and means for returning said last means to inoperative position immediately upon further opening of the throttle valve.

. 8. The combination with the intake manifold of an internal combustion engine, a carburetor connected thereto having a throttle valve and a vacuum lifted accelerating valve operating means, actuating means for said throttle valve and an air inlet valve for supplying air directly to the intake manifold, of means controlled by the pressure 7 conditions in the intake manifold for opening said air inlet valve when said throttle valve is returned to or moved towards idling position, and means operated with said last means for locking said accelerating valve operating means in vacuum lifted position while said air inlet valve is open.

9. The combination with the intake manifold of an internal combustion engine, a carburetor connected thereto having a throttle valve and a vacuum lifted accelerating valve operator, actuating means for said throttle valve and an air inlet valve for supplying air directly to the intake manifold, of means controlled by the pressure conditions in the intake manifold for opening said air inlet valve when said throttle valve is returned to or moved towards idling position, means operated with said last means for locking said accelerating valve operator in vacuum lifted position, means controlled by'the flow of air to the intake manifold for holding said previous means actuated until the engine speed approaches idling position or a position corresponding to the throttle valve opening, and means actuated with said pressure controlled means for holding said accelerating valve operator in vacuum lifted position until the engine approaches idling speed.

' 10. The combination with the intake manifold of an internal combustion engine, a carburetor connected thereto having a throttle valve, actuating means for the throttle valve and an accelerating assembly including a fuel valve, said assembly being connected tothe intake manifold so that the fuel valve is closed when the throttle valve is in idling position, of means for opening the intake manifold to the atmosphere when the throttle valve is at or moved toward idling position and the engine is operating at greater than idling speed and means for preventing the opening of the fuel valve when the intake manifold is open to the atmosphere.

EDWARD G. PARVIN. 

